Efficacy and safety of combination of poly-ADP-ribose polymerase inhibitor (PARPi) and chemotherapy compared with chemotherapy alone in treatment of recurrent ovarian carcinoma: a systematic review.

Platinum-based chemotherapy after surgical cytoreduction is the universal treatment for advanced ovarian cancer (OC), however, about eighty percent of patients experienced relapse and progression-free survival remained poor. Patients who relapsed within one year of treatment eventually become resistant to second-line chemotherapy. Poly-ADP-ribose polymerase inhibitors are a novel class of targeted therapy that could overcome these challenges by augmenting the chemotherapeutic activity of other cytotoxic agents. Cumulative Index to Nursing and Allied Health Literature (CINHAL), Cochrane and PubMed databases were searched for potentially relevant primary publications from 2011 to 2022 reporting on efficacy and safety of combination of a PARP inhibitor and chemotherapy versus chemotherapy in recurrent OC and reviewed. The outcomes of interest assessed qualitatively were progression-free survival (PFS) and grade 3 or higher adverse events (AEs) as measures of efficacy and safety respectively. Eight randomized controlled trials (RCTs) were included in the systematic review comprising 3,021 patients evaluated efficacy and safety of PARP inhibitors: Olaparib, niraparib and veliparib with combinations of bevacizumab, carboplatin, cisplatin, cediranib, cyclophosphamide and paclitaxel. 824 patients had 33 BRCA mutation while 1,430 had wild-type BRCA, an allele that confers increased risk of cancer. Most patients had platinum-sensitive cancers. There was significant prolongation of PFS with PARP inhibitor and chemotherapy combination compared to chemotherapy in all included trials except one which combined veliparib with cyclophosphamide. The prolongation of PFS was more remarkable in patients with BRCA mutation and occasionally patients with wild-type BRCA. Niraparib and veliparib were notably associated with grade 3 or higher anaemia, neutropenia, and thrombocytopenia, olaparib caused fatigue and gastrointestinal disturbances while bevacizumab and cediranib caused hypertension. This review suggested combined PARP inhibitor and chemotherapy significantly prolonged progression-free survival especially in patients with BRCA mutation compared to chemotherapy and the combined therapy is safe.